Rheostat



Jan. 30, 1923. 1,443,469. 1. GUTHRIE ET AL.

RHEOSTAT.

FILED AuG.4, 1922.

20' Jefe Patented Jan. 3o, 1923.

UNITED STATES JAMES GUTHRIE, OF ELYRIA, AND JOHN GUTHRIE-ASSIGNOR TO THE SIMMON LAND, OHIO, A CORPORATION OF OHIO.

PATENT. oF

annos'rar.

Application led August 4, 1922. Serial No. 579,598.

To all whom z't may concern:

Be it known that we, (1) JAMns'GU'rHRIn and (2) JOHN W. SiMMoNs, citizens of the United States, residing at (1) Elyria, and (2) Cleveland, in the county of (1) Lorain, and (2) Cuyahoga, and State of Ohio, have invented a certain newl and useful Improvement in Rheostats, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings.

This invention is anovel construction of rheostat or resistance device particularly adapted for use in connection with radio apparatus, although it will be understood that the device or the principle thereof can be used for other purposes.

The object of the invention is to provide an exceedingly cheap and simple construc' tion of rlieostat involving a resistance pile of carbon disks and a still provide a novel form of resistance pile and also a novel means of adjusting or regulating the resistance with ease and accuracy. With these various objects in view the invention F consists in the novel features of construction and in the manner of combining or arrange ing thev same, allfof which will. be ully/ described hereinafter and pointed out in the claims.

In the drawings formingl a. part of vthis specification Fig. 1 is a side elevation partly in section, illustrating a rheostat constructed in accordance with our invention; Fi .l .2 is a top plan view of the same; Fig. 3 is a transverse vertical section; Fig. 4 is a horizontall section on the line -4 4 of Fig.t v1; and Fig. 5 is a diagram of a curve indicating variations in resistance due to movement'of actuating means. i

In the practical embodiment of the invention there is employed a container or receptacle 10 preferably `cylindrical in form and made of porcelain or other suitable material.4

The bottom of this receptacle has a central *i aperture 11 through which .is passed the binding post 12 having the nuts 13 arranged thereon and the head of 'this binding post is preferably c'ountersunk into a` disk 14 of any suitable material. The upper end of thev further object is to cylindrical container is formed with a laterally projecting flange 15 which is preferably square or rectangular in shape as indicated in Fig. 2. Within the cylindrical porcelain container we arrange a resistance pile composed of alternate layers of perforate and I? imperforate carbon disks 16 and 17, respectively, Athese disks@ being quite thin and by making every other disk with acentral opening as indicated at 16a we are able to produce a pile composed of thin disks and which will 60 not tend to warp or get out of place; and by maintaining perfect contact between the series of disks, provide a better resistance element. Bearing upon the resistance pile of carbon disks is a plunger 18 having the lower 65 end 18@l and a coil spring 19 which surrounds the plunger` and bears upon this enlarged lower end exerts a `constant downward pressure upon the plunger and resistance pile, this spring bearing at its upper end upon a plate 2O which is rigidlyconnected to the top of the porcelain container by means of s'crews 20a, said plate having a central aperture through which the upper end ofthe plunger passes as most clearly. shown in F ig. 3. The plate 20 is formed with up wardly projecting ianges or wings 21 at the opposite ends thereof and working through theseA flanges is a rotary shaft 22 having a hand wheel-23 upon the outerend thereof. 80 By means of the forward flange the device can be rigidly connected to a portion 24 of the casing or panel which is preferablyv formed of some dielectric material. rIfhe shaft 22 has its inner end j ournaled in the in- 85 ner flange or wing 21 and is threaded as shown at 25 and carries thereon ai block 26 having a threaded hub portion 27. The bottom portion of this block is apertured or recessed as shown at 28, in order that said 90 block may move back and forth upontha, plate 2 0 and straddle the upwardly pro3ect ing end of the plunger rod. An actuating lever in the form'of a bail is 'connected to the upper= end of the plunger rod and 1n turn 95 bears with its upper. e d against the rear face-of the block 26. T `is lever is indicated at 30 and it will be noted that the lever coin-v upper end of .the .plunger rod. The parallel membersy are curved Sonthe arc'oi a circle and at their. upper ends where they meet the connecting portion theyy are turned iadially` this actuating lever curved on the arc of a circle'andactuating lo the same by. meansof the block 26 which `moves rearwardly9 the lever ulcrums upon the plate and lifts' the plun er rod against the compression spring 19k n makin-g this movement the lever isconstantly' shifting its l5 iulcrum portion of the lever is rolling upon the iat` plate and in this mannerv the variation in resistance is very gradual at tiret and in creases in a variable manner as most clearly 20 shown by the diagramA of Fig, 5., the curved line indmating by outwardly. ,By having of the curved line indicating the condition of greatest resistance. lt will benoted that ,the

M When the-.pile is .compressed as vshownin Figs. 1 and i-the' resistance is least and when pressure is-,relieved vthe lvresistance increases yaccording to the sanieurve By means oi the' arc shaped 'lever andthe -laterallymovableblock actuat/ed by the' shaft 22, we yare able to obtain exceedingly tine andfa'ccurate variationsin the resistance pile.

I t will be understood hat the lever bail 30 `1s Jformed of .a good varietyot wire which has some resiliency and consequently that in -40 connectionl withv thecompressiom spring 19 f -will' maintain'the ac'tuatin ylever 30 constantly. /in .engagement wit the Y'movable @block 2 6 while within itsrangeioi travel.

A 'blndlng o r'mected to lthe exfrear iiange QI-iatf-anyfdei' disk 14 at the bottom :of th" container and also with the enlargement' '18* Aat thelower :end of theplunger rod.

of rheostat -W given size of article and it.' will also. loe. noted that the very linest .variations' .of fthe resist'- 'ancecan be eiected.

a plunger Aout `el?. contact the circuit will'fbe 160 opened." fforated. j-By nsin per tacts between dis' fis' I warpingl of I' '.'damr mfbemployd increasing the point, orin otherjwords, the curved )Spin its upper end the. condi. tion ci least resistance and therlower end-- for the same, a plunger bearingupon said v,pile with a normal definite' pressure, connected to one end fof said plunger anda plunger.

perforated resistancedisks and 'orthesame, a plunger bearing'upon -said r pile with a normal definite pressure, connected at one end to 4said plunger and f lateral ymovable member ada ted .to engage s aid. lever forfthegpurpose ci) moving said 1p un 1 l r, 6. nia rheostat, a-container, aseriesof re- "sistaneef' units" arrangedtherein,a

It will thus. bessen; "at therein provided an exceedlnglyuslmple and-,inexpensiveorm the same,'

ch willprovidev or minimumv amount of resistance. foniar 'thepressurenpon' f 7. In a'rhe'ostat, a container, a vseries off 125g?)v quickly, easily'` and` acmrately Y.resistance units arranged therein,' a. plunger f resting upon said resistance.units,I aplate se- Furthermore by. completely` moving thev l' v *havngan'opening throug'li'whi Ifv desiredjallz-the can'be pei-m :forfeited 'disks linecom- 'j prevented cas'eof the disk, ndyd-isk :Gf-f laure"-v rv Sistance variations.' Y,

The 'form of 4lever bail can also be varied if desired to obtainlany-ratio of increase or decrease' desired. 1 f y Havingthus described our irpventionpwhat we claim's: y l 7.0

l.. ln var rheostat, aresistance pile com posed of alternate vperforated and imperio` rated resistance dis s.

2. ln a rheostat, a reslstance pilefy'com'-Y a posed of resistance disks, means for containing the same, rmeans for normally exerting l pressure thereom and means for varyin r `said pressure according to a. predetermme ratio.

a rheostat., a. resistance pile composed v of alternate perforated and imperforated resistance disks, and a container for the same, a plunger bearing upon said pile with anormal uniform -pressu're and means for I relieving said pressure with a gradual'in- 85 creasing variation. A f

' ein a rheostat, aresistance pile composed of a series of resistance disks and a container a' lever 90 l laterally movablemember ada ted\to engage said lever 'for the purpose o moving sald '5. In a'rheostatfa resistance pile composed 95 of a` series of alternate perforatedand 1m' a container a lever lmger 10B resting yuponfsaidreslstanceunitswi 'n the l 4containenj-a :flanged plate secuped tothe top pt saidcontainer, said plate having an open- 'gingithroughfwliich the'zendfof`v the plunger Pmltss pmg @sai'd ,plunger and exerting pressure afpressmre exerting member actuat- 11o .against1 said. p ate and .resistance units, a-

leverconnected at one end to said I@plunger .and 'fulcruming' upon lsaid plate, a a

terally movable member andv means for-`actuat1ng said member contacting 'with'n the said lever and causing the'- same lplunger and increase" or. decrease the resistance pile.

free-*end of to Jmoveth ,memberconnected to the\plun'ger and-begr. andleans carriedbyfitheyf ing uponfthe ,p1 te plate for-actuatmgsaid liftingmembe'n e '8. In -a' rheostaua cox'xtainer,y a seriesjioff-lsd resistance units arranged therein, a plunger free end of said lever, and means for movresting upon said resistance units, a plate in said member. v secured to the top of container and having n testimony whereof, we hereunto affix 10 an opening through which the end of plunour signatures.

5 ger projects, a curved lever connected to said plunger, said lever bearing upon the plate, JAMES GUTHRIE. e laterally movable member engaging the JOHN W. SIMMONS. 

